[PATCH 3/3] media: rc: Replace timeval with ktime_t in imon.c

From: Chunyan Zhang
Date: Thu Dec 18 2014 - 06:53:26 EST


This patch changes the 32-bit time type (timeval) to the 64-bit one
(ktime_t), since 32-bit time types will break in the year 2038.

I use ktime_t instead of all uses of timeval in imon.c

This patch also changes do_gettimeofday() to ktime_get() accordingly,
since ktime_get returns a ktime_t, but do_gettimeofday returns a
struct timeval, and the other reason is that ktime_get() uses
the monotonic clock.

This patch will use a new function 'ktime_ms_delta' which is introduced
in 1/3 of this patch-set to get the millisecond time difference.

Signed-off-by: Chunyan Zhang <zhang.chunyan@xxxxxxxxxx>
Acked-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxx>
---
drivers/media/rc/imon.c | 49 +++++++++++++----------------------------------
1 file changed, 13 insertions(+), 36 deletions(-)

diff --git a/drivers/media/rc/imon.c b/drivers/media/rc/imon.c
index b8837dd..a1e91d5 100644
--- a/drivers/media/rc/imon.c
+++ b/drivers/media/rc/imon.c
@@ -31,6 +31,7 @@
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/kernel.h>
+#include <linux/ktime.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
@@ -41,7 +42,6 @@
#include <linux/usb/input.h>
#include <media/rc-core.h>

-#include <linux/time.h>
#include <linux/timer.h>

#define MOD_AUTHOR "Jarod Wilson <jarod@xxxxxxxxxxxx>"
@@ -1158,29 +1158,6 @@ out:
return retval;
}

-static inline int tv2int(const struct timeval *a, const struct timeval *b)
-{
- int usecs = 0;
- int sec = 0;
-
- if (b->tv_usec > a->tv_usec) {
- usecs = 1000000;
- sec--;
- }
-
- usecs += a->tv_usec - b->tv_usec;
-
- sec += a->tv_sec - b->tv_sec;
- sec *= 1000;
- usecs /= 1000;
- sec += usecs;
-
- if (sec < 0)
- sec = 1000;
-
- return sec;
-}
-
/**
* The directional pad behaves a bit differently, depending on whether this is
* one of the older ffdc devices or a newer device. Newer devices appear to
@@ -1191,16 +1168,16 @@ static inline int tv2int(const struct timeval *a, const struct timeval *b)
*/
static int stabilize(int a, int b, u16 timeout, u16 threshold)
{
- struct timeval ct;
- static struct timeval prev_time = {0, 0};
- static struct timeval hit_time = {0, 0};
+ ktime_t ct;
+ static ktime_t prev_time;
+ static ktime_t hit_time;
static int x, y, prev_result, hits;
int result = 0;
- int msec, msec_hit;
+ long msec, msec_hit;

- do_gettimeofday(&ct);
- msec = tv2int(&ct, &prev_time);
- msec_hit = tv2int(&ct, &hit_time);
+ ct = ktime_get();
+ msec = ktime_ms_delta(ct, prev_time);
+ msec_hit = ktime_ms_delta(ct, hit_time);

if (msec > 100) {
x = 0;
@@ -1596,9 +1573,9 @@ static void imon_incoming_packet(struct imon_context *ictx,
int i;
u64 scancode;
int press_type = 0;
- int msec;
- struct timeval t;
- static struct timeval prev_time = { 0, 0 };
+ long msec;
+ ktime_t t;
+ static ktime_t prev_time;
u8 ktype;

/* filter out junk data on the older 0xffdc imon devices */
@@ -1692,10 +1669,10 @@ static void imon_incoming_packet(struct imon_context *ictx,
/* Only panel type events left to process now */
spin_lock_irqsave(&ictx->kc_lock, flags);

- do_gettimeofday(&t);
+ t = ktime_get();
/* KEY_MUTE repeats from knob need to be suppressed */
if (ictx->kc == KEY_MUTE && ictx->kc == ictx->last_keycode) {
- msec = tv2int(&t, &prev_time);
+ msec = ktime_ms_delta(t, prev_time);
if (msec < ictx->idev->rep[REP_DELAY]) {
spin_unlock_irqrestore(&ictx->kc_lock, flags);
return;
--
1.7.9.5

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